Latching mechanism



y 20, 1958 H. F. GEORGE 2,835,125

LATCHING MECHANISM Filed July 30, 1954 5 Sheets-Sheet l I II :5.l'w'nfenfar'. Ji'rr Feozya jl ,5 MM

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y 20, 1958 H. F. GEORGE 2,835,125

LATCHING MECHANISM Filed July so, 1954 s Sheets-Sheet s J2 4 15 Z 5/ Z4United States Patent LATCHING MECHANISM Harry F. George, Chicago, Ill.

Application July 30, 1954, Serial No. 446,718

6 Claims. (Cl. 70-146) This invention relates to improved latchingmechanism adapted for use in both metal and wood doors, and whileparticularly adapted "for use with metal screen doors, I wish itunderstood that it may be used insuch other connections to which it maybe adapted.

The present invention is an improvement over that disclosed in mycopending application Serial No. 350,681, filed April 23, 1953, nowPatent No. 2,764,014, issued September 25, 1956.

One of the important features of the present invention is theimpossibility of the operator locking himself or herself outaccidentally, as vfor example when accidentally setting the mechanism tolock, and then going out and slamming the door shut. However, themechanism is so made that it can be locked from the inside againstanyone opening the door from the outside. The latching mechanism can belocked by setting the mechanism in locked position from the inside andthe operator either staying inside or going out some other door, and,when a key operated lock is provided, the door can be locked andunlocked by a key from the outside. A further im portant feature is anovel compact arrangement of the parts such that the latching mechanismcan be factory assembled, can be quickly and easily installed inoperative position to the door, is reliable in operation, economical tomanufacture, and of pleasing appearance.

Among the objects of the present invention are; to provide a new andimproved latching mechanism; to provideslatching mechanism in which .itis impossible to lock oneself out accidentally; to provide latchingmechanism having locking means that can be set in locked position whenthetdoor is ajar and which will be moved team-locked position when thedoor is slammed shut; to provide latch- .ing mechanism in. which thedoor may be locked shut trom'the inside and which may :be unlocked onlyfrom the inside or by a they from the outside; to provide latchingmechanism especially adapted for the receptionof keyoperated meansaccessible from the outside, or such keyoperated means may be omitted ifdesired; to provide latching mechanism having unique interlockingfeatures between the bolt and the striker plate; to provide latch- .ingmechanism having a novel construction and arrangement of .latc'h boltand associated parts; to provide latch- *ing mechanism having novelmeans for securing the knob to :a square shaft; to provide latchingmechanism that may be factory assembled, has automatic latching, turnsleft or right, may :be applied to left and right hand doors of eithermetal or wood, and that has surface mounting with no mortising required;and such further objects, ad vantages and capabilities, inherentlypossessed by my in- Mention, as willlaterrmore fully-appear.

. My invention further resides in the combination, constnuction andarrangement of parts illustrated in the accompanying drawings, and whileI have shown therein preferred embodiments "I wish it understood thatthe same are susceptible of modification and change without departingfrom the spirit of my invention.

In the drawings:

Fig. l is a fragmentary horizontal transverse section through a metalscreen door and an adjacent portion of a door frame, and showing appliedto the door a latching mechanism embodying my invention.

Fig. 2 is a side elevation of my latching mechanism, looking toward theinside turning handle, and showing the inner configuration of the latchbolt in dotted lines. Fig. 3 is a side elevation of my latchingmechanism, looking toward the outside knob having a key-operated lockcylinder secured therein.

Fig. 4 is a vertical section on the line 44 of Fig. 1.

Fig. 5 is a vertical median section through the outside knob andadjacent portions of the door, showing the lock cylinder as having beenremoved from the knob, and a cover plate fixed in position in the lockcylinder hole.

Fig. 6 is a vertical median section through the latching mechanism ofFigs. 1-3, showing the lock cylinder secured in the outside knob andextending inwardlyfor operation of the locking mechanism by a key.

Fig. 7 is a vertical transverse section on the line 7-7 of Fig. 6.

Fig. 8 is a horizontal section, partly in elevation, taken on the line8-8 of Fig. 6.

Fig. 9 is a side elevation of the latching mechanism housing plate,showing its interior end construction in dotted lines. a

Fig. 10 is an edge view looking toward the right hand edge of Fig. 9.

Fig. 11 is a detail side elevation of the latch bolt.

Fig. 12 is anedge view looking toward the right hand edge of Fig. 11.

Fig. 13 is a view similar to Fig. 6, but omitting the lock cylinder, andshowing the outside knob secured to a square shaft which in turn isfixed to rotate with the inside handle.

Fig. 14 is a horizontal section, partly in elevation, taken on the line14-14 of Fig. 13.

Fig. 15 is a transverse section on the line 15-.15 of Fig. 13.

Fig. 16 is a transverse section on the line 16-16 of Fig. 13.

Fig. 17 is a side elevation of the shiftab le actuator bar of Fig. 13.,

Fig. 18 is an edge view looking toward the righthand edge of Fig. 17.

Fig. 19 is a side elevation of a washer for positioning between theactuator bar and the hub of the inside turning handle and having detentmeans for cooperating with complemental detent means in the actuatorbar.

Fig. 20 is an edge view looking toward the right hand edge of Fig. 19.

Fig. 21 is a side elevation of a slip washer for straddling a groove inthe square shaft and bearing against the side of the actuator baropposite from the side contacted by the washer of Fig. 19.

Fig. 22 is an edge view looking toward the right hand edge of Fig. 21.

In the present invention I have provided a latching mechanism that canbe equipped with a key-operated lock cylinder as in Figs. 1-3 and 6-8,or in which the lock cylinder can be omitted as in Figs. 5 and 13-16.However, in both forms, with and without the lock cylindenthe latchhousing, the latch bolt, and the inside operating mechanism, are of thesame construction.

The general construction includes an inside turning handle 5, an outsideknob 6, and latching mechanism, with either a tubular shaft or a squareshaft extending through from the outside knob to and through thelatching mechanism, depending on whether, or not, .a lock cylinderis tobe incorporated in the assembly. The main control portions of thelatching mechanism are housed in a latch housing 1, being operativelyheld therein by a cover plate 2 formed at each of its two ends with anintegral ear 3, which ears are seated in end notches 4 in the latchhousing and fastened therein by springing or bending after the controlparts have been properly assembled in the housing. The latch housing 1has at each end an offset portion 7, the amount of such offset from themain portion of the housing being such as to provide for the receptionof the moving parts and permit of their movement within the space 8formed within the outer wall of the housing between said outer wall andthe cover plate 2. The latch housing plate 1 has a central circular holeA to rotatably receive the tubular shaft 20.

At each of the four corners of the housing space 8, the housing wall isformed with an inwardly extending short flange 9 for purposes later morefully explained. The offset end portions 7 of the housing 1 are eachformed with a central hole 10, and the cover plate 2 at each end isformed with a hole 11 respectively in registry with holes 10, to receivescrews 12, or other suitable means, for securing the housing to theinner face of the door 13. Slidably mounted in the space 8 withinhousing 1 is a Hat latch bolt member 14 formed centrally at one edgewith an upstanding ear 15 formed with a latch lip 16 inclined at anangle toward the plane of the door. As seen in Fig. 1.2 the ear 15 for ashort distance from where it joins the flat body of the latch bolt isnarrower than its outer end and lip 16. This narrower neck portion isslidably mounted in the recess 17 formed in the adjacent edge of thehousing 1, so as to slidably mount the latch lip 16 outside of thehousing and the flat body portion of the latch bolt 14 inside of thehousing.

The flat latch bolt member 14 is of a length to snugly but slidably movelaterally in the housing in a direction toward the right (latchingdirection) as viewed in Fig. 7, by the compression springs 18 seatedbetween the adjacent corner flanges 9, and the shoulders 19 formed bycutting out portions of the latch bolt flat body to receive the springs18. Movement of the latch bolt member 14 in a direction toward the left(unlatching direction) as viewed in Fig. 7, is effected by rotation ofeither the inside handle or the outside knob 6, which, in the form shownin Figs. 1-8, are connected together by the tubular shaft 20 which atone end is either integral with or fixed to the hub of the inside handle5, and to the other end of which tubular shaft the outside knob issecured both by the threads 21 and the set screw 22. As seen in Fig. 7,the flat latch bolt member 14 is formed in its portion inside of thehousing with an irregularly shaped opening 23 through which the tubularshaft 20 extends.

As seen in Figs. 6-8, the shaft 20 is formed in its opposite walls withrectangular openings in that portion of the shaft within the interior ofthe latch housing 1, through which opposite openings is slidably mountedan actuator bar 24. Fixed in each of the Opposite end portions of bar 24is a laterally extending pin 25, which pins extend respectively througharcuate slots 26 formed in the outer housing wall, for sliding movementtherein, to permit limited rotation of shaft 20 in either direction.Pins 25, after passing through slots 26, also pass through registeringopenings in the lock plate 27 which is provided with a central opening28 through which shaft 20 passes, opening 28 being of a substantiallylarger diameter than the shaft in the direction of the actuator bar 24,so that when the pins 25 are in the center longitudinally of the arcuateslots 26, they may be moved downwardly, as viewed in Fig. 9, into thenotches 29 formed in slots 26 to lock the shaft against rotation withrelation to the housing, as later more fully explained. As will beunderstood in Fig. 6, pins 25, on the outer face of lock plate 27 arerounded to form a head 30, whereby the lock plate 27 on the outside ofthe housing, and the actuator bar 24 on the inside of the housing, willmove together as a unit for both rotational and radial movement as thepins move appropriately in the arcuate slots and the notches 29. At theopposite ends of the lock plate 27 are formed outstanding flanges 31 toserve as finger rests so that the lock plate can be pushed downwardly orupwardly for locking and unlocking purposes respectively, as desired.

As viewed in Fig. 7, the mid-portion of the left hand edge of theactuator bar 24 is formed with a pair of spaced apart notches 32 and 33to serve as detents to yieldably receive the small projection 34 on thespring member 35 which is held by bent ends between the adjacent edge ofthe actuator bar and the ends of the openings in the shaft. This permitsthe actuator bar 24 to be pushed radially through the shaft in onedirection or the other by a push in the appropriate direction on theoutside lock plate 27 and be held in such position by the spring detentuntil a force is exerted against the lock plate to move the actuator barin the opposite direction. When the actuator bar 24 up in the positionshown in Fig. 7, the pins 25 will ride in the arcuate slots 26, andenable the bar 24 to be rocked with the tubular shaft 20, and move thelatch bolt 14 to retracted position when the shaft is rotated in eitherdirection. For illustration, when the shaft 20 is rotated in a clockwisedirection as viewed in Fig. 7, the lower end of the actuator bar 24 willpush against the adjacent edge portion of the opening 23 in the latchbolt 14 and retract the latch bolt to the left against the compressionof springs 18. When the turning force on shaft 20 is released, springs18 will. return the latch bolt to the right to projected position. Whenthe shaft 20 is rotated in a counterclockwise direction as viewed inFig. 7, the upper end of the actuator bar 24 will push against theadjacent edge portion of the opening 23 in the latch bolt and retractthe latch bolt to the left against the compression of springs 18, whichwill return the latch bolt to projected position when the turning forceon theshaft is released. It is thus seen that the latch bolt may beretracted by turning the inside handle or outside knob in eitherdirection.

The configuration of opening 23 in the latch bolt plate 14 is such as togive the necessary play to the top and bottom portions of the actuatorbar 24 while the latch bolt is being retracted as described above, andalso to form a cam portion 36 so positioned that when the actuator bar24 is in its downward position with detent projection 34 engaged indetent notch 33, the bottom end of bar 24 will be opposite said camportion 36 and approximately in contact therewith. At the same time pins25 will have been drawn downwardly into notches 29 which is lockingposition and will lock actuator bar 24 against turning or rocking withrelation to stationary housing 1, and also prevent shaft 20 fromrotating, which in turn will prevent the latch bolt 14 from beingretracted from the outside of the door. However, should the door beslightly ajar, and the lock plate 27 be accidentally moved downwardlyinto locking position, it would be impossible for the operator to lockhimself out by slamming or otherwise forcing the door shut, because thelatch-lip 16 would be cammed inwardly by the inclined stationary lip 37of the striker plate 38 which is fixed to the door frame 39. This wouldforce the latch bolt inwardly and cause the cam portion 36 on the latchbolt to push against the curved bottom end of the actuator bar 24 andforce the latter upwardly to move the pins 25 out of the locking notches29, thus unlocking the shaft and permitting normal operation of thelatch bolt by rotation of the shaft. This action will be understood byreferring to Figs. 7 and 8. As seen in Figs. 7 and 16, when the latchbolt is in fully projected position under the action of the compressionsprings 18, the rear side edges of the actuator bar 24 will be incontact with the rear vertical edges of the latch bolt opening 23 to actas a stop for the latch bolt to limit the amount of its projection.

Referring to Figs. 3 and 6-8, the present latching mechanism may have alock cylinder 40 secured in place in the tubular shaft 20, so that thedoor may be locked from the inside by the lock plate 27 against beingopened from the outside, and unlocked. from the: outside. only. by akey. It mayof course be unlocked from. the inside by manual operation ofsaid loci plate 27.. As the lock cylinder 40 is of conventional type itneed not be described. in detail except to point out that it isprovidedwith an extension 41 rotatably mounted in the interior of tubular shaft20, which extension at its inner endis formed with a cylindrical head 42provided in its inner. end face with an axially extending eccentricallylocated: pin 43 located in an enlarged recess 44 formed centrally in theedge of the actuator bar toward the latch lip 16. Recess 44 is enoughlarger than the diameter of pin 43 to provide for the necessary movementof the pin in moving. theactuator bar into and out of locking positionduring rotation of the lock cylinder from the outside of the door byakey, and

to permit the keyto be returned to its central removal position, as willbe understood in Fig. 7, in which the actuator bar is shown inunlockedposition, and the pin 43 in.

position ready to move the actuator bar into locked position uponrotation of the key inthe. lock: cylinder in the appropriate direction.Also as will be understoodin Fig. 7, the length of the recess 44 issufiicient to permit of movement of the actuator bar into either lockedor unlocked position by manual operation of the lock plate 27 from theinside, independently of the lock cylinder and key, andyet permit suchmovement of the actuator bar by the key and lock cylinder from theoutside when desired.

If desired, in the form of Figs. 1-4 and 6-8, the lock cylinder 40 maybe omitted, and the hole in the outer end of the tubular shaft 20, inthecenter of the outer knob 6, may be covered up by the closure cap 45.having resilient fingers 46 that will hold the cap in place whenidriveninto said hole, asshown in Fig. 5. Cap 45 may be removed if it isdesired at a later date to install a loclt cylinder 40 in the tubularshaft. This gives the user the selection of using or omitting the lockcylinder as desired.

In the form shown in Figs. 13-22, there is no tubular shaft or lockcylinder, but instead, a square shaft 47 is rigidly fixed to the hub ofthe. inside handle to extend through the latching mechanism, through ahole in the door, and part way into a square hole in the outside knob6'. In this form the actuator bar 24' is of slightly different form inthat the square shaft 47 passes through an elongated rectangular opening48 in the actuator bar, see Figs. 16 and 17, and the detent means forreleasably holding the actuator bar 24' in locked and unlocked positionsare arranged somewhatdifferently. Otherwise thelatching mechanism is thesame as inthepreviously described form shown in Figs. 1-12.

In the form of Figs. 13-22, a washer '49, of copper, brass, or othersuitable material, and formed with a centrally located square hole 50 ofa size to snugly fit over square shaft 47, is slid along the squareshaft into contact with the inner face of the hub of the inside handle 5to bear thereagainst, and on its opposite face to bear against theadjacent face of the actuator bar 24,.this being made possible by theinner end of the hub of the inside handle 5 passing through the centralhole A in thehousing plate 1. 0n opposite sides of hole 50 the washer isformed below its horizontal center line, as viewed in Fig. 19, with twoindentations 51 which are punched therein so as to emerge from the sidenext to the actuator bar 24 as a pair of spaced detent projections 52,see Fig, 20. The actuator bar 24' on its face next. to Washer 49,, isformed with two vertically spaced pairs of small recesses 53 and 54, sothat when this bar is pushed upwardly by the lock plate 27 the pair ofprojections 52 on the washer 49 will enter the pair of detent recesses53 in the actuator bar and hold the pins 25 in line with the arcuateslots 26 to permit normal latching operations. When the actuator bar ispushed downwardly by the lock plate 27 the pair of projections 52 on thewasher 49 will enter the pair of detent recesses 54 in the actuator barand hold the pins 25 in the notches 29 to lock the latch bolt againstmovement in the housing until the actuator bar is again moved 6 upwardlyeither by the lock plate 27 being manually, pushed upwardly, or by thecam shoulder 36 as explained above.

It should be noted that when the latch bolt 14 is in its maximumprojected position, the actuator bar 24' (or 24) is in vertical positionas viewed in Figs. 7 and 16, which positions the pins 25 directly overnotches 29 to be pushed thereinto by a downward push on lock plate 27',in both forms, or by turning the key in the: form of Figs. 1-8, in thelock cylinder in the appropriate direction, when it is desired to lockthe shaft against rotation. As will be understood in Figs. 16 and 17,the elongated rectangular opening 48 in the actuator bar 24 is of awidth to be slidable radially over the square shaft 47, and of a lengthto permit the actuator bar to be movable downwardly, as viewed in Fig.'16, into locked position, and upwardly into unlocked position. Theactuator bar is shown in Fig. 16 as being in the unlocked position.

in the form of Figs. 13-22, as well as in the form of Figs. 1-8, thecontrol parts of the latching mechanism, are housed in the housing 1,and held in operative posi tion therein by the cover plate 2 which isfastened to the housing by the ears 3 as previously explained. As willbe understood the latching mechanism parts will be properly assembled inthe housing 1, after which the cover plate will be fastened in place.This enables the parts to be assembled at the factory, and sold. inassembled units ready to be applied to the inside face of the door. Asuitable hole will be provided in the door for the reception of theshaft.

It is also pointed out that as soon as the washer 4) and the actuatorbar 24', in the form of Figs. 13-22, are properly assembled in thehousing, they will be held in such proper assembly by insertion of aslip washer 55, see Fig. 21, into a circumferential groove 56 formed inthe sides of the square shaft 47 in such position to hold the hub. ofthe inside handle, the washer 49, and the actuator bar 24, snuglytogether for rotation as a unit, and also permit sliding of the actuatorbar into and out of locking position, see Figs. 13 and'14. The slipwasher 55 will: be frictionally held in the circumferential groove 56,,and will be applied tothe shaft before the cover plate. 2. is secured tothe housing.

In the form of Figs. 13-22, see Figs. 13 and 1.4,, the outside knob 6isformed with a central axially extending hole 57, square inv crosssection, to snugly receive the projecting end of the square shaft 47.Connecting the inner end of hole 57 with the outer face of knob 6 is ahole 58,. round in cross section, and beveled at its outer end toreceive the beveled neck of the slotted head 59 of the: threaded screwstem 60 which is threadably screwed into the threaded axial hole 61extending a. distance into the square shaft. Mounted against the outerend of the square shaft 47 is a spring washer 62 sufficiently thin topermit the threaded stem 60 to be threaded therethrough. Washer 62 onone side of the central hole therein is radie ally split from the holeto the adjacent outer edge, with the two portions of the Washer onopposite sides of the split being slightly offset axially with relationto. the screw stem 60, whereby when the screw stem is screwed into thesquare shaft to properly position the knob. with relation. to theadjacent door surface, the screw stem will be under tension so as toprevent its loosening up.

The latching mechanism of the present invention may be applied to, anyof many types. of doors, and while, for illustrative purposes only, ithas been shown herein as applied to a screen door having tubular metalmarginal portions, to which it is well adapted, I wish it understoodthat it may be applied to wooden doors, and any other type of door towhich. it may be adapted. As pointed out earlier herein, it may beprovided with or without a lock cylinder, as desired. Also the presentlatching mechanism is so constructed as to make it impossible toaccidentally lock the door from the inner side, go out, slam the doorshut, and find oneself locked out. Also as pointed out above, thecontrol parts of the latching mechanism are mounted as a unit in thehousing over which is secured a cover plate, so that the device may befactory assembled, and be quickly and easily applied to either left orhigh hand doors, for turning of the handle or knob in either a left orright hand direction, and for use in both metal and wood doors.

In the present invention no mortising is required to be made in the doorfor applying the latching mechanism thereto. Also the latch bolt andstriker plate are formed with angular lips that will be in interlockingposition with relation to each other when the door is closed and thelatch bolt projected, because of the latch bolt lip 16' extending at anangle toward the plane of the latch bolt and laterally outwardly of thehousing, and the striker plate lip extending at an angle away from theplane of the latch bolt and laterally toward the housing, as seen inFigs. 1, 8 and 14.

Having described my invention, 1 claim:

1. Latching mechanism, comprising a housing having a front plate, a backcover plate and an inner cavity, a latch bolt laterally slidable in saidcavity and having an enlarged opening, spring means for normally urgingthe latch bolt to projected position, a shaft rotatably extendingthrough said front plate, back cover plate and latch bolt opening, anactuator bar in said latch bolt enlarged opening and connected to saidshaft for rotation therewith and radially slidable with relationthereto, means for selectively moving the actuator bar in one directionradially of the shaft for holding the shaft against rotation and formoving the actuator bar in the opposite direction radially of the shaftfor releasing the shaft for rotation for moving the latch bolt toretracted position, and means for securing the back cover plate to thefront plate.

2. Latching mechanism, comprising, a housing adapted to be securedagainst a side surface of a door, a fiat latch bolt laterally slidablein said housing and having an enlarged opening therein, a rotatableshaft extending at right angles through the housing and latch boltopening, an actuator bar in said housing connected with said shaft forrotation therewith and radial sliding movement with relation thereto,said actuator bar extending radially from both sides of the shaft, saidlatch bolt having a recess in line with the actuator bar and openinginto said enlarged opening, said housing having an outer wall formedwith a laterally extending slot and a notch extending at right angles tothe laterally extending slot and intercommunicating therewith, a lockmember on the outer face of the housing outer wall, a pin connecting thelock member and the actuator hat through said slot and notch, wherebymovement of the pin into said slot will permit rotation of the shaft forretracting the latch bolt, and movement of the pin into said notch willlock the shaft against rotation at which time the end of the actuatorbar will be in said recess in the latch bolt.

3. Latching mechanism as claimed in claim 2, in which the forward edgeof said recess in the latch bolt is camshaped, whereby a strong inwardforce on the projected end of the latch bolt will cause the cam-shapededge of the recess to move the actuator bar to move the pin to unlockedposition so that the shaft may be rotated.

4. Latching mechanism, comprising, a shaft having turning means on eachend thereof, a housing through which the shaft rotatably extends, a flatlatch bolt laterally slidable in said housing and having an enlargedopening throughwhich the shaft extends, an actuator bar in the enlargedopening of the latch bolt and connected to said shaft for rotationtherewith, said actuator bar being radially slidable with relation tothe shaft, a lock plate on the outside wall of the housing, said outsidewall having a laterally extending arcuate slot having in its midposition an intercommunicating notch extending in a direction radiallyof the shaft, and a pin connecting the lock plate and the actuator barand movable in said arcuate slot and notch, whereby when the pin is inthe arcuate slot rotation of the shaft will retract the latch bolt, andwhen the lock plate is moved to carry the pin into said radiallyextending notch the shaft will be locked against rotation so that thelatch bolt cannot be retracted by the shaft.

5. Latching mechanism as claimed in claim 4, including a second arcuateslot and notch in said outer wall, and a second pin connecting the lockplate and actuator bar and movable in the second slot and notch, saidarcuate slots being on opposite sides of the shaft, and said notchesbeing so located that a straight line passing through the centersthereof will pass through the center of the shaft.

6. Latching mechanism, comprising, a thin fiat housing open at its frontand rear side edges and adapted to be secured to the inside flat fact ofa door, a latch bolt laterally slidable in said housing and having anenlarged opening therein, a tubular shaft extending through saidenlarged opening in the latch bolt and having a turning member securedto its inner end and a turning member secured to its outer end, anactuator bar radially slidable through said shaft and rotatabletherewith, said actuator bar being positioned in the enlarged opening inthe latch bolt, said housing having an outer wall formed with alaterally extending slot and an intercommunicating notch extending in adirection radially of the shaft, a lock member on the outer face of thehousing outer wall, a pin connecting the lock member and the actuatorbar and movable in said slot and notch for sliding the actuator barradially in the shaft in one direction for normal latching operationwhen the pin is in the laterally extending slot, and in the oppositedirection for locking the shaft against rotation with relation to thehousing when the pin is in said notch, and a lock cylinder mounted insaid outer turning member and having an extension extending in thetubular shaft to the actuator bar and having connection therewith forsliding the actuator bar radially in the shaft for locking and unlockingthe shaft against and for rotation by a key from the outside.

References Cited in the file of this patent UNITED STATES PATENTS276,942 Watson May 1, 1883 297,660 Ballin Apr, 29, 1884 1,001,082Samuelson Aug. 22, 1911 1,173,007 Leusley Feb. 22, 1916 1,662,119 LewisMar. 13, 1928 2,216,467 Falk Oct. 1, 1940 2,726,533 Quinn Dec. 13, 1955FOREIGN PATENTS 85,990 Switzerland July 16, 1920 467,207 Great BritainJune 14, 1937

